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<td><b><dl><dt>Berkeley DB Reference Guide:<dd>Access Methods</dl></b></td>
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<p align=center><b>Duplicating a cursor</b></p>
<p>Once a cursor has been initialized (for example, by a call to
<a href="../../api_c/dbc_get.html">DBcursor-&gt;get</a>), it can be thought of as identifying a particular
location in a database.  The <a href="../../api_c/dbc_dup.html">DBcursor-&gt;dup</a> method permits an application to
create a new cursor that has the same locking and transactional
information as the cursor from which it is copied, and which optionally
refers to the same position in the database.</p>
<p>In order to maintain a cursor position when an application is using
locking, locks are maintained on behalf of the cursor until the cursor is
closed.  In cases when an application is using locking without
transactions, cursor duplication is often required to avoid
self-deadlocks.  For further details, refer to
<a href="../../ref/lock/am_conv.html">Access method locking conventions</a>.</p>
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